acpi: add checking for NULL early param
[linux-3.10.git] / drivers / acpi / tables.c
1 /*
2  *  acpi_tables.c - ACPI Boot-Time Table Parsing
3  *
4  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  *
24  */
25
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/smp.h>
29 #include <linux/string.h>
30 #include <linux/types.h>
31 #include <linux/irq.h>
32 #include <linux/errno.h>
33 #include <linux/acpi.h>
34 #include <linux/bootmem.h>
35
36 #define PREFIX                  "ACPI: "
37
38 #define ACPI_MAX_TABLES         128
39
40 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
41 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
42
43 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
44
45 static int acpi_apic_instance __initdata;
46
47 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
48 {
49         if (!header)
50                 return;
51
52         switch (header->type) {
53
54         case ACPI_MADT_TYPE_LOCAL_APIC:
55                 {
56                         struct acpi_madt_local_apic *p =
57                             (struct acpi_madt_local_apic *)header;
58                         printk(KERN_INFO PREFIX
59                                "LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
60                                p->processor_id, p->id,
61                                (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
62                 }
63                 break;
64
65         case ACPI_MADT_TYPE_IO_APIC:
66                 {
67                         struct acpi_madt_io_apic *p =
68                             (struct acpi_madt_io_apic *)header;
69                         printk(KERN_INFO PREFIX
70                                "IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
71                                p->id, p->address, p->global_irq_base);
72                 }
73                 break;
74
75         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
76                 {
77                         struct acpi_madt_interrupt_override *p =
78                             (struct acpi_madt_interrupt_override *)header;
79                         printk(KERN_INFO PREFIX
80                                "INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
81                                p->bus, p->source_irq, p->global_irq,
82                                mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
83                                mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
84                         if (p->inti_flags  &
85                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
86                                 printk(KERN_INFO PREFIX
87                                        "INT_SRC_OVR unexpected reserved flags: 0x%x\n",
88                                        p->inti_flags  &
89                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
90
91                 }
92                 break;
93
94         case ACPI_MADT_TYPE_NMI_SOURCE:
95                 {
96                         struct acpi_madt_nmi_source *p =
97                             (struct acpi_madt_nmi_source *)header;
98                         printk(KERN_INFO PREFIX
99                                "NMI_SRC (%s %s global_irq %d)\n",
100                                mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
101                                mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
102                                p->global_irq);
103                 }
104                 break;
105
106         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
107                 {
108                         struct acpi_madt_local_apic_nmi *p =
109                             (struct acpi_madt_local_apic_nmi *)header;
110                         printk(KERN_INFO PREFIX
111                                "LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
112                                p->processor_id,
113                                mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK  ],
114                                mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
115                                p->lint);
116                 }
117                 break;
118
119         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
120                 {
121                         struct acpi_madt_local_apic_override *p =
122                             (struct acpi_madt_local_apic_override *)header;
123                         printk(KERN_INFO PREFIX
124                                "LAPIC_ADDR_OVR (address[%p])\n",
125                                (void *)(unsigned long)p->address);
126                 }
127                 break;
128
129         case ACPI_MADT_TYPE_IO_SAPIC:
130                 {
131                         struct acpi_madt_io_sapic *p =
132                             (struct acpi_madt_io_sapic *)header;
133                         printk(KERN_INFO PREFIX
134                                "IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
135                                p->id, (void *)(unsigned long)p->address,
136                                p->global_irq_base);
137                 }
138                 break;
139
140         case ACPI_MADT_TYPE_LOCAL_SAPIC:
141                 {
142                         struct acpi_madt_local_sapic *p =
143                             (struct acpi_madt_local_sapic *)header;
144                         printk(KERN_INFO PREFIX
145                                "LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
146                                p->processor_id, p->id, p->eid,
147                                (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
148                 }
149                 break;
150
151         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
152                 {
153                         struct acpi_madt_interrupt_source *p =
154                             (struct acpi_madt_interrupt_source *)header;
155                         printk(KERN_INFO PREFIX
156                                "PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
157                                mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
158                                mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
159                                p->type, p->id, p->eid, p->io_sapic_vector,
160                                p->global_irq);
161                 }
162                 break;
163
164         default:
165                 printk(KERN_WARNING PREFIX
166                        "Found unsupported MADT entry (type = 0x%x)\n",
167                        header->type);
168                 break;
169         }
170 }
171
172
173 int __init
174 acpi_table_parse_entries(char *id,
175                              unsigned long table_size,
176                              int entry_id,
177                              acpi_table_entry_handler handler,
178                              unsigned int max_entries)
179 {
180         struct acpi_table_header *table_header = NULL;
181         struct acpi_subtable_header *entry;
182         unsigned int count = 0;
183         unsigned long table_end;
184
185         if (!handler)
186                 return -EINVAL;
187
188         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
189                 acpi_get_table(id, acpi_apic_instance, &table_header);
190         else
191                 acpi_get_table(id, 0, &table_header);
192
193         if (!table_header) {
194                 printk(KERN_WARNING PREFIX "%4.4s not present\n", id);
195                 return -ENODEV;
196         }
197
198         table_end = (unsigned long)table_header + table_header->length;
199
200         /* Parse all entries looking for a match. */
201
202         entry = (struct acpi_subtable_header *)
203             ((unsigned long)table_header + table_size);
204
205         while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
206                table_end) {
207                 if (entry->type == entry_id
208                     && (!max_entries || count++ < max_entries))
209                         if (handler(entry, table_end))
210                                 return -EINVAL;
211
212                 entry = (struct acpi_subtable_header *)
213                     ((unsigned long)entry + entry->length);
214         }
215         if (max_entries && count > max_entries) {
216                 printk(KERN_WARNING PREFIX "[%4.4s:0x%02x] ignored %i entries of "
217                        "%i found\n", id, entry_id, count - max_entries, count);
218         }
219
220         return count;
221 }
222
223 int __init
224 acpi_table_parse_madt(enum acpi_madt_type id,
225                       acpi_table_entry_handler handler, unsigned int max_entries)
226 {
227         return acpi_table_parse_entries(ACPI_SIG_MADT,
228                                             sizeof(struct acpi_table_madt), id,
229                                             handler, max_entries);
230 }
231
232 /**
233  * acpi_table_parse - find table with @id, run @handler on it
234  *
235  * @id: table id to find
236  * @handler: handler to run
237  *
238  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
239  * run @handler on it.  Return 0 if table found, return on if not.
240  */
241 int __init acpi_table_parse(char *id, acpi_table_handler handler)
242 {
243         struct acpi_table_header *table = NULL;
244
245         if (!handler)
246                 return -EINVAL;
247
248         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
249                 acpi_get_table(id, acpi_apic_instance, &table);
250         else
251                 acpi_get_table(id, 0, &table);
252
253         if (table) {
254                 handler(table);
255                 return 0;
256         } else
257                 return 1;
258 }
259
260 /* 
261  * The BIOS is supposed to supply a single APIC/MADT,
262  * but some report two.  Provide a knob to use either.
263  * (don't you wish instance 0 and 1 were not the same?)
264  */
265 static void __init check_multiple_madt(void)
266 {
267         struct acpi_table_header *table = NULL;
268
269         acpi_get_table(ACPI_SIG_MADT, 2, &table);
270         if (table) {
271                 printk(KERN_WARNING PREFIX
272                        "BIOS bug: multiple APIC/MADT found,"
273                        " using %d\n", acpi_apic_instance);
274                 printk(KERN_WARNING PREFIX
275                        "If \"acpi_apic_instance=%d\" works better, "
276                        "notify linux-acpi@vger.kernel.org\n",
277                        acpi_apic_instance ? 0 : 2);
278
279         } else
280                 acpi_apic_instance = 0;
281
282         return;
283 }
284
285 /*
286  * acpi_table_init()
287  *
288  * find RSDP, find and checksum SDT/XSDT.
289  * checksum all tables, print SDT/XSDT
290  *
291  * result: sdt_entry[] is initialized
292  */
293
294 int __init acpi_table_init(void)
295 {
296         acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
297         check_multiple_madt();
298         return 0;
299 }
300
301 static int __init acpi_parse_apic_instance(char *str)
302 {
303         if (!str)
304                 return -EINVAL;
305
306         acpi_apic_instance = simple_strtoul(str, NULL, 0);
307
308         printk(KERN_NOTICE PREFIX "Shall use APIC/MADT table %d\n",
309                acpi_apic_instance);
310
311         return 0;
312 }
313
314 early_param("acpi_apic_instance", acpi_parse_apic_instance);